1. Field of the Invention
The present invention relates to a data communication apparatus which allows an external apparatus to register an address in an address book as a list of addresses used upon sending and transfer of data, and also allows the external apparatus to refer to the address book, and a method of controlling the same.
2. Description of the Related Art
An image forming apparatus such as an MFP (Multi Function Peripheral) includes an address book used to register addresses used upon sending and transfer of data. In order to allow a plurality of image forming apparatuses to commonly access the address book, the address book can be delivered to another image forming apparatus via a network. A technique for generating, at the time of delivery of the address book to other image forming apparatuses, an address book suited to each apparatus by distinguishing addresses to be commonly distributed to all image forming apparatuses and those to be individually distributed to each apparatus has been proposed (for example, Japanese Patent Laid-Open No. 2007-188166).
As a method of allowing a plurality of image forming apparatuses to access an address book of an image forming apparatus, a technique that allows a given image forming apparatus to directly refer to an address book of another image forming apparatus via a network is also known.
Assuming that a file management system in an image forming apparatus has a file server function, an external apparatus, which is connected to the image forming apparatus via a network, can access the file management system in the image forming apparatus as a normal file server. Protocols provided as the file server function include, for example, SMB (Server Message Block), CIFS (Common Internet File System), WebDAV (Web-based Distributed Authoring and Versioning), and FTP (File Transfer Protocol).
When the image forming apparatus serves as the file server function, an address provided by the file server function by the image forming apparatus itself can be registered and accessed as a destination in an address book of the image forming apparatus. In this case, as the address of the file server provided by the image forming apparatus, a loopback address can also be designated. For example, if it is assumed that the file server function of the image forming apparatus (having, for example, an IP address “168.0.0.1”) allows an external apparatus to access a folder “share” managed by its file management system. In this case, a loopback address “¥¥localhost¥share” or “¥¥127.0.0.1¥share” can be designated in place of registering an SMB path “¥¥168.0.0.1¥share” in the address book. However, when a loopback address (“localhost”, “127.0.0.1”, or “::1”) of the image forming apparatus itself is registered in the address book of the image forming apparatus, the following problems are posed.
When an address book possessed inside an image forming apparatus (server) is registered from an external image forming apparatus (client), an address as a loopback address may be registered in the address book of the server. In this case, it is unknown whether the address to be registered intends that of the server or client. As a result, although the client attempts to register a loopback address in the address book of the server, since the loopback address is an address of another image forming apparatus, data may be transferred to the other apparatus corresponding to the address.
With the technique described in Japanese Patent Laid-Open No. 2007-188166 above, upon distributing an address book from a server to all image forming apparatuses, the address book can be distributed while distinguishing addresses to be distributed to all the image forming apparatuses, and those to be distributed individually. However, that technique cannot distinguish whether an address designated as a loopback address designates the server, a specific client, or an image forming apparatus as an operation source at the time of sending/transfer processing.